Kubo Keratosis Abstract (IMAGE) Kobe University Caption To develop porokeratosis, people need two damaged copies of the gene, “two hits.” One they acquire either from their parents (left) or through epigenetic silencing early in their fetal development (middle and right). This predisposes them to developing the disease but in itself is not symptomatic. In the case of epigenetic silencing, individuals are mosaics of predisposed cells (green area), that derive from the one where the silencing occurred, and unaffected cells. A second defect in the other copy of the gene leads to the outbreak (red dots). Credit KUBO Akiharu Usage Restrictions Credit must be given to the creator. License CC BY Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.